RICHMOND - During the bittersweet farewell to high school Thursday night, seniors Andrea Mallory and Liliana Valenzuela donned their red caps and gowns, ascended the steps of the Richmond Convention Center stage and grasped the hand of their principal. After four years at Richmond High, both girls captured a spot on the honor roll. Both plan to attend college. Both dream of entering medicine; Mallory for physical therapy, Valenzuela for nursing. When Mallory descended the wooden steps, she left proudly clutching a facsimile of the diploma she will pick up next week. Valenzuela held her own certificate. But in a...